After a year, Oracle is now telling everyone some of the necessary knowledge of Oracle, I hope that novices will go away from the detour. Surmling as follows: 1: Oralce8i previous versions do not support temporary tables. Oracle's temporary table is a special table, establish a session object for each user, and the data accessed per user is different. Two types of On Commit Delete Rows (deleted when submitted) and on Preserve delete Rows (deleted data at the end of the session). 2: Oracle9i previous version does not support cross-connect, if it is 9i previous versions need to be handled through special means. In addition, Oracle9i will support the SQL92 standard after the left and right connections! 3: Oracle8i previously does not support Whare House, 8i called snapshot, 9i is a materialization attempt. The materialized view is a actual table, which is very different from the ordinary view we usually used. 4: Oracle9i did not support the CASE statement before. Ha ha. . This is indeed a bit exaggerated, but it is a bit problem in actual ~~ `This is my own experience summary. I hope to use it for everyone ~~ `
